The purpose of this research is to identify the effect of Loan to Deposits Ratio (LDR), Firm Size, and Debt to Equity Ratio (DER) towards Return on Assets (ROA) at National Private Commercial Banks (Foreign Exchange) for the period: 2018-2021. The number of samples consists of 12 banks obtained by using purposive sampling technique. The data used in this research is secondary data in the form of financial statements of National Private Commercial Banks (Foreign Exchange) taken from the official website of the Financial Services Authority (OJK) for the period: 2018 – 2021. The data analysis model used is multiple linear regression analysis the hypothesis test uses data analysis technique, namely t Test, F Test, and Coefficient of Determination (Adjusted R2). Based on the result of the F Test, it is found that the LDR, Firm Size, and DER variables simultaneously have a significant effect on ROA. Based on the results of the t Test, the LDR and Firm Size variables partially have a significant effect on ROA, whereas the DER variable partially has no significant effect on ROA National Private Commercial Banks (Foreign Exchange) for the period: 2018-2021. Based on the result of Coefficient of Determination (Adjusted R2), it shows that LDR, Firm Size, and DER have an effect of 42,7% on ROA whereas the rest (100% - 42,7% = 57.3%) is influenced by other reasons outside the model.